In daily life, there are a large number of cases where a determined quantity of contents need to be taken out of the contents accommodated in a container and then used. For example, there are many cases where a predetermined quantity of liquid or powder contents need to be taken from the contents accommodated in a container and then used, such as a case where cooking oil or various types of seasoning need to be measured upon cooking food, a case where a determined dose of liquid medicine needs to be taken, a case where a mouthwash needs to be taken into a cap and used to gargle the mouth, a case where a quantity of detergent or fabric softener suitable for the quantity of laundry needs to be taken from a container and then used, etc.
When measurement is required as described above, a method of taking contents from a container by tilting a container toward a measuring cup or a container cap on which graduations are printed or carved while observing the graduations with the eye has been used hitherto in most cases.
Meanwhile, according to a report, a survey found that, although a dose within a dose error range of 5% was considered to be a regular dose in regard to the taking of medicine, a dose error of 25.8% occurred in connection a measuring cup on which graduations were printed, and a dose error of 23.3% occurred in connection a measuring cup on which graduations were carved. In particular, most dose errors take the form of excessive doses, and thus the risk of overdoses is high. Furthermore, there are many cases where excessive quantities of detergent or fabric softener larger than appropriate quantities are used, and thus water is wasted and the excessive use becomes a cause of water contamination.
Since there are frequent cases where quantitative use is not sufficiently observed for the reason that measurement is inconvenient or inaccurate notwithstanding that quantitative use is required as described above, some schemes for improvement have been proposed.
Korean Patent Application Publication No. 2004-0023480 of “patent document 1” discloses an inner cap in which a cover part configured to open or close the outlet of a container is coupled to the upper end of the container, graduations configured to measure the quantity of contents of the cover part are marked, and a desired quantity of contents are discharged into the inside of the cover part and used in the state where the cover part has been opened. However, the inner cap of patent document 1 still has problems in that the quantity of contents discharged is not uniform due to viscosity and the like during a process of discharging contents into the cover part because the inner cup simply performs only the function of a measuring cup and in that accuracy is not ensured because measurement is made depending on the graduations.
Furthermore, Korean Utility Model Application Publication No. 1986-0009713 of “patent document 2” discloses a quantitative outflow lid. The lid of patent document 2 is configured such that an opening and closed valve functions as a check valve. Furthermore, when liquid contents are discharged from a container body, contents are discharged through a discharge hole having a small inner diameter by compressing the container body in the state where the lid has been opened and then a container has been tilted. However, the lid of patent document 2 has a problem in that measuring error is significant because the quantity of contents to be discharged is determined by the compressing force with which the container is compressed and thus a deviation resulting from the elasticity of the container body, the grasping power of a user, or the like is significant.
Furthermore, Korean Patent Application Publication No. 2004-0039224 of “patent document 3” discloses a cap that accommodates a check valve and has a contents storage space. However, patent document 3 employs a check valve simply for the purpose of enabling children or the elder to easily use a container because contents do not spill even when the container falls over, but does not take into account a quantitative outflow function.